Members of the Women's Institute are being asked to help crack down on adverts selling sex in newspapers, it emerged today.

A spokeswoman for the group, which has more than 200,000 members across the country, told Radio 5 Live members would be encouraged to look out for adverts and write letters of complaint to editors if they found them.

She said: "There are an estimated 4,000 females currently living in the UK who have trafficked to work on the street and off the street as prostitutes.

"Many of these women, some in their early teens, have been tricked and abducted from their own country and forced to live a life of exploitation and cruelty once they arrive in the UK."

She said the adverts, often placed in local newspapers, were the most common way used by men to access sexual services.

She added: "We have so many members we believe we can make a difference on the ground and in our local community."